地上生物圏における二酸化窒素固定のための統一的な枠組み
Benjamin Z Houlton1, Ying-Ping Wang, Peter M Vitousek
1Biological Sciences, Stanford University, Stanford, California 94305, USA. bzhoulton@ucdavis.edu
Nature
|June 20, 2008
まとめ
シンビオティック・ダイナトロゲン (N(2)) 固定は,植物が窒素をリン獲得のために投資しているため,リンが限られている熱帯地域で好まれている. 高緯度の気温は,成熟した森林の固定を制限する.
科学分野:
- エコロジー エコロジー エコロジー
- バイオジオケミストリー バイオジオケミストリー
- 植物科学 植物科学について
背景:
- 二酸化窒素 (N) の固定は,地球環境の変化に対する生態系の反応に不可欠である.
- N(2) 固定理論と,陸上のバイオームにおける観測との間には,不一致がある.
- N2固定植物の豊富さは地理的に異なるが,熱帯ではより多く見られる.
研究 の 目的:
- 地球上のN2固定装置のグローバル分布を説明する統一的な枠組みを提示する.
- 多様なバイオームにわたる共生的なN(2) 固定を促す要因を解明する.
- 気候変動と高濃度のCO2に対する生態系の反応を予測するための基礎を提供すること.
主な方法:
- 植物による炭素,窒素,の獲得における検討されたトレードオフ.
- バイオ物理学的メカニズムで統合された生地化学サイクリング.
- N(2) 固定率と種分布に影響を与える要因を分析した.
主要な成果:
- シンビオティックなN(2) 固定剤は,リンが限られた熱帯サバンナや森林で優位性があります.
- の獲得のための窒素投資は,熱帯の持続的なN2固定のために不可欠です.
- 温度による制約N(2) 高緯度の成熟林における固定率と種.
結論:
- 生地化学的および生体物理的要因を結びつける枠組みは,地上のN(2) 固定パターンを説明する.
- これらのパターンを理解することは,地球規模の変化に対する栄養素に制限された生態系の反応を予測する鍵です.
- この研究は,変化する環境条件下で,陸上の生態系におけるN(2) 固定の役割についての洞察を提供します.
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